For the $…which is the better wheel time wise on 1/2IM or full IM?
You know what Crowrunner?
This may be an impossible question to answer. I own both and like them both. I must say I do like an all carbon rim (advantage: Zipp). Hed hubs require a little less babying than Zipp. That’s nice.
Both wheelsets are excellent- best in class. I hate to give you a mamby-pamby answer, but you won’t go wrong with either. It’s kind of like, which is better? Porsche or BMW?
Porsche. That’s a no brainer. 
Both are prolly arguably amongst the best sets out there. You wouldn’t go wrong with either.
If I had my choice, I’d go withn a set of 909’s…all carbon…very light and strong. I’ve got a set of 404’s and a 909 disc and I did not race the the 404 rear wheel at all last season. The disc is just much better…even in the windiest conditions. I would say go for the 909’s instead of the 404’s. If $$ permits…